[clang-tools-extra] [clang-tidy] performance-enum-size should ignore enums within extern "C" (PR #178233)

[via cfe-commits]

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@@ -106,3 +106,15 @@ enum class EnumClassWithoutValues : int {};
 enum EnumWithoutValues {};
 
 }
+
+extern "C" {
+enum ExternCEnum {
+    ec1,
+    ec2
+};
+
+typedef enum {
+    tec1,
+    tec2
+} IgnoredTypedefEnum;
+}
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EugeneZelenko wrote:

```suggestion
} // extern "C"
```

https://github.com/llvm/llvm-project/pull/178233